I. Field of the Invention
The present invention relates to an image forming apparatus of the type forming a toner image on an image carrier, then transferring the toner image to an intermediate transfer body (primary transfer hereinafter), and then transferring the toner image to a paper or similar recording medium (secondary transfer hereinafter).
II. Discussion of the Background
An image forming apparatus of the type described is conventional. I conducted a series of researches and experiments with such an image forming apparatus in order to further enhance the quality of the toner image finally transferred to a recording medium. The researches and experiments showed that at the time of the primary transfer of a toner image, the linear velocity of the surface of an image carrier and that of the surface of an intermediate transfer body sharply change and cause the image to be dislocated on the intermediate transfer body. This problem is particularly serious with a color image forming apparatus which sequentially forms toner images of different colors on an image carrier while sequentially transferring them from the image carrier to an intermediate transfer body one above the other; the dislocation of the individual toner images on the intermediate transfer body critically deteriorates the quality of the final image transferred to a recording medium.
It is therefore an object of the present invention to provide an image forming apparatus capable of insuring a high quality image by reducing the dislocation of an image.
In accordance with the present invention, an image forming apparatus includes an image carrier for forming a toner image on its surface thereof. An intermediate transfer body has a surface to which the toner image is transferred from the surface of the image carrier by primary transfer. A first electric field forming member forms between the image carrier and the intermediate transfer body a static electric field for effecting the primary transfer of the toner image. A second electric field forming member forms between the intermediate transfer body and a recording medium a static electric field for transferring the toner image from the surface of the intermediate transfer body to the recording medium. A dot image forming device forms a number of scattered dot toner images in the form of fine dots on the surface of the image carrier. The dot toner images are transferred from the surface of the image carrier to the image area of the intermediate transfer body.